When Justin Trowbridge comes to work at Columbia Sportswear Co., the Lancaster, Pa.-based store manager wears his commitment to diversity on his nametag. Instead of just reading “Justin,” the 28-year-old’s badge also includes the words “he/him/his.”

Some big business is increasingly embracing the practice of sharing individual pronouns in the workplace as part of diversity initiatives to support co-workers who may be transgender, or nonbinary colleagues who identify as neither male nor female. A growing number of employees...

When Justin Trowbridge comes to work at Columbia Sportswear Co., the Lancaster, Pa.-based store manager wears his commitment to diversity on his nametag. Instead of just reading “Justin,” the 28-year-old’s badge also includes the words “he/him/his.”

Some big business is increasingly embracing the practice of sharing individual pronouns in the workplace as part of diversity initiatives to support co-workers who may be transgender, or nonbinary colleagues who identify as neither male nor female. A growing number of employees are adding their pronouns to everything from email signatures to Zoom profiles—often at their company’s urging.

The practice, though, is far from a workplace norm and has met with puzzlement and uncertainty in some quarters as workers try to navigate this new terrain.

“I’m just a straight middle-class white boy,” says Mr. Trowbridge. “I was like, how do I fit into this?”

“‘If we make everyone feel more included, like they belong, that’s where we’re going to see a new shift in actual diversity.’”

— Justin Trowbridge, Columbia Sportswear store manager

Reading material from his company’s HR department about what has been termed allyship convinced Mr. Trowbridge that adding pronouns to his nametag would help create a more supportive atmosphere in the store, one that backs the notion that a person’s gender identity doesn’t always match their physical appearance.

“If we make everyone feel more included, like they belong, that’s where we’re going to see a new shift in actual diversity,” he says.

Around 240 retail employees have chosen to do the same, said Columbia Sportswear, which offered its 2,500 U.S. retail associates the option to add pronouns to their badges this summer, an effort spearheaded by the company’s LGBT-affiliated employee resource group.

“We’re not mandating anybody make that decision,” says Richelle Luther, the company’s chief human resources officer. “It’s something that needs education.”

Other companies also said they aren’t requiring people to share their pronouns. Even so, some professionals say that once they see others using pronouns in their email signatures and profiles, they feel social pressure to do the same.

The growing number of employees sharing their pronouns mirrors wider corporate efforts to do more to support diverse employees, a push that accelerated after George Floyd’s murder last year. Companies promoting the practice say they’re treading carefully, aware that many people may not understand the reasons behind it or agree it’s necessary, and may not be comfortable adopting it themselves.

“It’s extremely new,” says Randi Bryant, chief diversity and inclusion officer at the software company Freshworks in San Mateo, Calif. Ms. Bryant estimates around half of her 4,300-person company have incorporated pronouns into their email signatures, but adds the company isn’t asking all employees to do so.

“To insist that somebody or everybody use pronouns, that’s performative,” she says, adding that she hopes employees feel naturally curious when they see others using pronouns, and begin to educate themselves on why.

LinkedIn rolled out a pronouns field for its 200 million U.S. users in March; to date, more than 1.6 million members have chosen to add theirs, the company says, noting greater adoption in industries such as public policy, philanthropy, online media and communications. Zoom and Slack also recently created functions that allow users to add pronouns to their profiles, with 16,420 organizations and companies with paid Slack accounts so far adopting the feature.

There are an estimated 1.4 million transgender adults in the U.S.—0.6% of the adult population—as well as many people who identify as nonbinary, according to researchers at the Williams Institute, a research group at the UCLA School of Law that studies sexual-orientation and gender-identity policy.

More Americans now say they personally know someone who is transgender: 42%, up from 37% in 2017, according to a new Pew Research Center survey. Over a quarter of Americans now say they know someone who goes by gender-neutral pronouns such as “they,” up from 18% in 2018. Celebrities who have recently come out as transgender or nonbinary, including Elliot Page and Demi Lovato, have also helped increase awareness.

At the same time, their identities might not be known among friends and co-workers, says Alyss Weissglass of Oakland, Calif., a software engineer at research and development cloud platform Benchling, who identifies as female.

“People don’t see us. They don’t know when there are trans people around,” says Ms. Weissglass, who transitioned in 2016. After nearly three years at her current workplace, she says she’s pretty sure even some of the co-workers she works most closely with don’t know she’s transgender, something she’s chosen not to share too widely.

She says she appreciates that many of her company’s executives and colleagues share their pronouns in their signatures, which makes her use of pronouns less conspicuous. “The needle is moving,” she says.

A McKinsey & Co. study from last year shows that LGBT workers experience more obstacles to advancement, and trans people in particular are prone to report that they don’t feel like they can talk about themselves or their lives outside of work.

Such a feeling of alienation contributes to high rates of turnover: McKinsey’s research found trans people are more likely to frequently think about leaving their company (32% vs. 21%), with 18% saying they expected to stay at their current employer for less than a year, more than double the figure for cisgender people.

Given such statistics, Wynne Nowland, CEO of insurance brokerage Bradley & Parker in Melville, N.Y., says an emphasis on pronouns isn’t enough.

“Sometimes these symbolic gestures make me nervous,” says Ms. Nowland, who transitioned in 2017. “Are we putting pronouns in our email signatures but not really having the inclusive practices where it counts?” she asks, adding that unless companies also focus on ensuring transgender and nonbinary employees are hired and promoted, such efforts can ring hollow.

“‘It’s being used for status points for people who have some sort of a guilt complex.’”

— Thomas Irre, runs an IT consulting company

In Winchester, Va., Thomas Irre, who runs an IT consulting company, says it irritates him to see connections on LinkedIn and elsewhere add pronouns to their profiles. While Mr. Irre says he supports equal treatment for transgender people, he says the moves feel inauthentic when adopted by people with no connections to the trans community.

“It’s being used for status points for people who have some sort of a guilt complex,” he says, adding that he’s not convinced it makes much of a difference for the people it’s intended to help.

Jenny Dearborn, chief people officer at the 1,000-person marketing automation company Klaviyo in Boston, Mass., which asks all employees to share pronouns when speaking in all-hands meetings, says it’s a meaningful act, especially given the heated competition for talent.

“Whatever is super important to college kids today is going to be super important to new-hire employees two years from now,” she said. “It’s imperative for the corporate world to adapt—and adapt fast if you want to stay relevant as an employer.”

Still, some workers say they’re holding back in professional settings. Akshat Poddutoori, a computer science major in West Lafayette, Ind., socially uses the pronouns “they/them” and dresses female around friends. During a summer internship at a consulting company, they used male pronouns and dressed male throughout the experience, as they were raised, to avoid unwanted attention.

“You don’t want to be outcasted or looked at differently because of the decisions you’ve made,” they say.

Write to Te-Ping Chen at te-ping.chen@wsj.com